Replace home picture and favicon by JHipster logo

Fix #671
Fix copy of images

Fix #671
Merge branch 'master' of github.com:ggaulard/generator-jhipster into ggaulard-master
Fix chrome warning by defining more complete media query for retina display like
Add comment to explain waiting for autoprefixer update
Merge pull request #676 from ggaulard/master

Replace home picture and favicon by JHipster logo
First version with one-to-one and many-to-many relationships. UI still needs to be worked on, as well as edge cases.

Work in progress #665 #670
Merge branch 'ggaulard-master'
Add default serialVersionUID
Generate DTOs for updating the entity, and a mapper to handle.
Capitalize field names
Include BigDecimal if required
Add DateTime serializer